Meron Ehud: Mechanisms of Species Diversity Change in Stressed Environments

The
impacts of environmental changes on species diversity, and thus on
ecosystem function and stability, is a central topic of current
ecological research. While such changes may independently affect animal
and plant species, plants standout in being primary producers; by
storing solar energy in chemical compounds they constitute the basal
trophic level of the food chain that animal species, including humans,
depend on. Plant communities respond to environmental changes at
different scales. At the landscape scale, where symmetry breaking
vegetation patterns appear (Fig. 1), a transition from one pattern
state to another may take place (Animation 1). At smaller, single-patch
scales, environmental changes may affect inter- and intra-specific
plant interactions. Using a mathematical modeling approach, we
developed a theory of plant communities in water limited system, and
are currently using it to highlight mechanisms of species diversity
change in
response to climate changes and disturbances. Special attention is
given to mechanisms that involve different levels of organization, e.g.
mechanisms by which pattern transitions at the landscape level affect
plant interactions and species richness at the single-patch level.

Animation 1: Model
simulation showing a transition from a banded vegetation pattern to a
spotted pattern induce by a local clear-cut disturbance. Downhill
direction is to the right. Produced by Erez Gilad.
Can't see the movie? here it is in animated GIF.